It is well known that increasingly high turbine operative temperatures have made it necessary to cool hot turbine parts. A number of conventional turbine engine constructions employ impingement cooling schemes for cooling the outer portion of stationary turbine shrouds. While cooling improves the overall efficiency of the turbine engine, some leakage occurs which reduces efficiency, as unnecessary overflow of cooling air is wasted and reduces overall turbine engine efficiency.
Accordingly, there is a need to provide an improved cooling for gas turbine engines, particularly for cooling a stationary turbine shroud.